US3964085A
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Method for fabricating multilayer insulator-semiconductor memory apparatus
Assignee: AT&T Inc
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Filing: 1975-08-18
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Granted: 1976-06-15
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Expires: 1995-08-18
Abstract
Abstract An SI 1 I 2 M (semiconductor-insulator 1 -insulator 2 -metal) memory structure, containing an impurity such as tungsten concentrated in a region including the interface ("I 1 I 2 ") region between the I 1 and I 2 region, is fabricated by depositing an oxide of the impurity, such as tungsten trioxide, on the then exposed, I 1 layer prior to fabricating the I 2 layer. The oxide of the impurity, such as tungsten trioxide, can be advantageously deposited by means of reactive evaporation.
Inventors
- 👤 Dawon Kahng
- 👤 Ernest Edward La Bate
- 👤 Martin Paul Lepselter
- 👤 Joseph Raymond Ligenza
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:07
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/69; G; G11; G11C; G11C16/00; G11C16/02; G11C16/04; G11C16/0466; H10D64/00; H10D64/01; H10D64/031; H10D64/037; H10N; H10N70/00
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
61 words
A semiconductor-insulator 1 -insulator 2 layered structure made by a process which includes the step of depositing an oxide of a metallic impurity on the then exposed surface of the insulator 1 layer, prior to the fabrication of the insulator 2 layer, in an amount yielding between about 10 14 and 4 × 10 15 metallic impurity nuclei per square centimeter.
Claim 2
Dependent Claim
61 words
A semiconductor-insulator 1 -insulator 2 layered structure made by a process which includes the step of depositing an oxide of a metallic impurity on the then exposed surface of the insulator 1 layer, prior to the fabrication of the insulator 2 layer, in an amount yielding between about 10 14 and 4 × 10 15 metallic impurity nuclei per square centimeter.
Claim 3
Dependent Claim
78 words
A semiconductor-insulator 1 -insulator 2 -metal layered structure made by a process including the steps of a. forming the insulator 1 layer on the semiconductor layer; b. depositing an oxide of a metallic impurity on the then exposed surface of the insulator 1 layer in an amount yielding between about 10 14 and 4 × 10 15 nuclei of the metallic impurity per square centimeter; followed by c. forming the insulator 2 layer on the insulator 1 layer.
Claim 4
Dependent Claim
78 words
A semiconductor-insulator 1 -insulator 2 -metal layered structure made by a process including the steps of a. forming the insulator 1 layer on the semiconductor layer; b. depositing an oxide of a metallic impurity on the then exposed surface of the insulator 1 layer in an amount yielding between about 10 14 and 4 × 10 15 nuclei of the metallic impurity per square centimeter; followed by c. forming the insulator 2 layer on the insulator 1 layer.
Claim 5
Dependent Claim
35 words
The structure of claim 2 in which the semiconductor is a silicon wafer, the insulator 1 layer is silicon dioxide grown on a major surface of the silicon wafer, and the metallic impurity is tungsten.
Claim 6
Dependent Claim
16 words
The structure of claim 2 in which the oxide of the metallic impurity is tungsten trioxide.
Claim 7
Dependent Claim
102 words
In a method for fabricating a memory apparatus comprising a semiconductor insulator 1 -insulator 2 -metal layered structure which contains metallic impurities in a predetermined molecularly dispersed surface concentration, without clumping which would form a Fermi level of the metallic impurities, in an interface insulator region (including the interface of the insulator layers), said impurities in a concentration supplying suitable states for the capture of electronic charges in said region, the step of depositing molecules of an oxide of the metallic impurity on the then exposed surface of the insulator 1 layer in an amount yielding said surface concentration of metallic impurities.
Claim 8
Dependent Claim
102 words
In a method for fabricating a memory apparatus comprising a semiconductor insulator 1 -insulator 2 -metal layered structure which contains metallic impurities in a predetermined molecularly dispersed surface concentration, without clumping which would form a Fermi level of the metallic impurities, in an interface insulator region (including the interface of the insulator layers), said impurities in a concentration supplying suitable states for the capture of electronic charges in said region, the step of depositing molecules of an oxide of the metallic impurity on the then exposed surface of the insulator 1 layer in an amount yielding said surface concentration of metallic impurities.
Claim 9
Dependent Claim
60 words
The method of claim 1 in which the oxide of the metallic impurity is tungsten trioxide and in which the step of depositing said tungsten trioxide is carried out in an ambient at a predetermined pressure of oxygen in which a heated tungsten body is located at a predetermined distance from said then exposed surface of the insulator 1 layer.
Claim 10
Dependent Claim
28 words
The method of claim 2 in which the surface concentration corresponds to between about 1 × 10 14 and 4 × 10 15 tungsten nuclei per square centimeter.
Claim 11
Dependent Claim
11 words
The method of claim 1 in which the metal is tungsten.
Claim 12
Dependent Claim
27 words
The method of claim 8 in which the surface concentration is between about 1 × 10 14 and 4 × 10 15 tungsten nuclei per square centimeter.
Claim 13
Dependent Claim
25 words
The method of claim 9 in which the surface concentration is between about 5 × 10 14 and 2 × 10 15 per square centimeter.
Claim 14
Dependent Claim
125 words
In a method for fabricating a semiconductor insulator 1 -insulator 2 -metal layered structure, in which the semiconductor is essentially silicon and in which the insulator 1 layer is essentially silicon dioxide, and in which a first interface insulator region (including the interface of the insulator layers) contains metal impurity nuclei which are dispersed in said insulator region without clumping which would form a Fermi level of the metal impurity, the step of depositing molecules of an oxide of the metal impurity on the then exposed surface of the insulator 1 layer to a surface concentration corresponding to between about 1 × 10 14 and about 4 × 10 15 of said metal impurity nuclei per square centimeter prior to depositing the insulator 2 layer.
Claim 15
Dependent Claim
125 words
In a method for fabricating a semiconductor insulator 1 -insulator 2 -metal layered structure, in which the semiconductor is essentially silicon and in which the insulator 1 layer is essentially silicon dioxide, and in which a first interface insulator region (including the interface of the insulator layers) contains metal impurity nuclei which are dispersed in said insulator region without clumping which would form a Fermi level of the metal impurity, the step of depositing molecules of an oxide of the metal impurity on the then exposed surface of the insulator 1 layer to a surface concentration corresponding to between about 1 × 10 14 and about 4 × 10 15 of said metal impurity nuclei per square centimeter prior to depositing the insulator 2 layer.
Claim 16
Dependent Claim
26 words
The method of claim 11 in which the said surface concentration is between about 5 × 10 14 and 2 × 10 15 per square centimeter.
Claim 17
Dependent Claim
12 words
The method of claim 12 in which the metal impurity is tungsten.
Claim 18
Dependent Claim
12 words
The method of claim 11 in which the metal impurity is tungsten.
Claim 19
Dependent Claim
16 words
The method of claim 14 in which the oxide of the metal impurity is tungsten trioxide.
Claim 20
Dependent Claim
9 words
The product made by the process of claim 11.
References Cited (Backward Citations)
US3665423A
Cited
US3877054A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-15 | 1979-12-15 | 1980-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-15 | 1983-12-15 | 1984-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-15 | 1987-12-15 | 1988-06-15 | $7700.00 | Window Closed / Lapsed |